Hydrofluoroolefin (HFO) such as trifluoroethylene (HFO-1123) and 2,3,3,3-tetrafluoropropene (HFO-1234yf) has a small global warming potential (GWP), so that in recent years, it has been largely expected as a new refrigerant which takes the place of difluoromethane (HFC-32) and 1,1,1,2,2-pentafluoroethane (HFC-125) being greenhouse effect gas.
Conventionally, as a method of producing HFO-1123, there has been known a method in which relatively inexpensive 1,1,1,2-tetrafluoroethane (HFC-134a) is used as a raw material. Further, as a method of producing HFO-1234yf, there has been known a method in which hydrofluorocarbon (HFC) such as 1,1,1,2,2-pentafluoropropane (HFC-245cb) or 1,1,1,2,3-pentafluoropropane (HFC-245eb) is used as a raw material.
For example, Reference 1 (JP-A H10-505337) discloses a method of producing HFO-1123 by causing dehydrofluorination reaction of HFC-134a while using metal fluoride or metal oxide as a catalyst. In the method of producing disclosed in Reference 1 (JP-A H10-505337), HFC-134a being a raw material and source gas containing nitrogen gas as diluent gas are supplied to a heating reaction band, and the dehydrofluorination reaction of HFC-134a is caused in the presence of catalyst in the heating reaction band, to thereby produce a composition containing HFO-1123.